Unit ventilator



March 28, 1933. v w. SHURTLEFF 1,903,143

UNIT VENTILATOR Filed Oct. 3, 1930 2 Sheets-Sheet l @Zgf mum \mnuuuuu 10 My m I ness. f

March 28, 1933. w. SHURTLEFF 1,903,143

UNIT VENTILATOR I Filed 001:. 5, 1930 2 Sheets-Sheet 2 Patented Mar. 28, 1933 UNITEDTSTA'TES PATENT; OFFICE WIIIFRED SHURTLEFF, OF MOLINE, ILLINOIS, ASSIGNOB TO THE- HERMAN NELSON GOR- PORATION, OF MOLINE, ILLINOIS,\A CORPORATION OF ILLINOIS UNIT VENTILATOR Application filed October 3, 1980. Serial No. 488,202.

This invention relates to unit ventilators of the general type now extensively used for the heating of school rooms or other places of public assembly, as well as ofiices and homes, and in which provision is made both for the re-circulation of indoor air and for the admission of external air, in order to maintain proper conditions within the room.

Although unit ventilators are adapted for use under numerous conditions, 'it is ordinarily necessary that they be especially designed with reference to the requirements of a school room.

In school installation it is desirable andto architectural and structural requirements.

In these circumstances, it is customary to proportion the unit ventilator in such a way as to afford the required radiating surface without unduly obstructing the aisle or extending above the level of the window ledge, which results in a relatively low and shallow structure without limitation as to length.

In certain types of construction, it has been customary to provide a by-pass' around the enclosed radiatorv and to afford a damper control for this passage, which permits a mixture of heated indoor air and by-passed external air to be discharged into the room. This arrangement, however, is frequently objectionable on account of the excessive depth required to afford room for the bypass, and in certain more recent constructions the practice has been followed of regulating the heatingintensity of the radiator, or of shutting off one or more sections of the radiator to prevent overheating of the air stream,

while at the same time providing for admis sion either of indoor air or ,of external air, or of both simultaneously.

In unit ventilators which omit the b -pass principleiand provide for the regulatlon of vention will be evident from the the heating intensity, difliculty has been experienced by reason of a failure to uniformly, heat the alr currents discharged into the room, with the result that streaks of cold .air have been discharged from certain portions of the ventilator concurrently with streaks of heated air from other portions,

with resulting discomfort to the occupants able and dangerous drafts.

The present invention is designed to overof the room and the generation'of undesir- -come these difficulties by so constructing and arranging the radiator sections that, irrespective of the number of sections in service for the time being, the air current, whether indoor or outdoor air, or a mixture of the two, will be of uniform temperature when discharged into the room.

The present invention relates to the ar-.

rangement and correlation of the radiator to the inletpassages, to the relation of the radiator to the fan and outlet, and to the general structure of the unit ventilator as awhole.

Other objects and details of thegresent inescription thereof in conjunction with the accompanyin drawin s, wherein,- igure 1 1s a view of the radiator, with the outer wall on the inner or room side removed; Fig. 2 is a top plan view of-the unit ventilator; 1

Fig. 3 is a sectional plan view taken on line 33ofFig.1;'

liig. 4 is an endview of the unit ventilator; an

Fig. 5 is a sectional elevation taken on line -.5 of Fig.1.

The ventilator as a whole is housed within a rectangular boxlike casing, comprising a frontwall 10'which faces inwardly toward the room, a rear wall 11, end walls 12 and 13,

The rear wall of the casing, near the bottom thereof, has outwardly pro ecting therefrom a boxlike duct 16, which when the ventilator is in service extends through an aperture in the wall, preferably located below the level of the window casing, and furnishes an inlet for the admission of external air. The passage through the external air duct is controlled by a louver l? which, as shown, consists-of several leaves or sections that may be suitably connected together for adjustment, although the particular formation of the louver may be changed or modified without varying the general structure or mode of operation of the device as a whole.

The front wall, near its base, is apertured to provide a grille 18 fronting inwardly to ward the room for admission of indoor air, to be re-circulated through the heating and ventilating unit.

The inlets for inner and external air both admit air to the base of the casing, and at this point a segmental gate valve 19 is provided which extends from end to end of the casing and is centrally pivoted at points 20 to the respective end walls of the casing.

The gate valve is proportioned and dimensioned to be swung either from the solid line position of Fig. 5 to the dotted line position, or to any intermediate position, depending upon the adjustment required to provide for the inflow of inner or external air, or a mixture of the two.

As shown, the gate valve, when swung upwardly to either .of its extreme positions, coacts with either of two flanges 21, one of such flanges inwardly extending from the front wall and one from the rear wall, and presenting their inner edges in position to lie closely adjacent to the curved wall of the gate in order to prevent leakage of air past the gate when moved to one or the other of its extreme positions of adjustment. The gate may be adjusted by a handle or other suitable means which it is not deemed necessary to illustrate or describe in detail.

Immediately above the area subtended by the gate valve in its range of movements is located a group of radiator sections which in the present instance are three in number, comprising a front section 22, an intermediate section 23, and a rear section 2%.

Each of the radiator sections is of the wedge core radiator type shown and described in the Otis and Shurt-lefi' patent, No. 1,707,564, issued April 2, 1929, which comprises a wedge shapedcore 25 and a large number of thin metallic fins or plates 26 threaded onto the core in closely spaced relation to one another and closely abutting the core to afford an intimate metal to metal contact for the purpose of increasing the radiating effect.

The group of radiator sections extends completely from end to end and from side to side of the casing, and is supported at a point immediatelv above the flanges21, so that air admitted from below must of necessity pass upwardly through the radiator sections in order to find egress from the casing. The ends of the radiator sections are connected in series by a pair of return bends 27 screwed onto the radiator nipples which extend outwardly through the respective end walls and are suitably coupled to the adjacent cores in such a way as to afford a continuous sinuous passage which extends first in one direction through the front radiator section 22, thence oppositely through the intermediate radiator section 23, and thence back through the rear radiator section 2 1 to a steam trap 28.

Although I have shown a Wedge core radia tor for purposes of exemplification, it is not the intention to limit the invention necessarily to a radiator of this type, since other forms of radiator units, arranged in conformity with the plan or principle of the present invention, may be substituted in lieu of the wedge core type.

The radiator group thus disposed forms in effect a partition through the casing, and above the radiator group are located fans 29-29 which are secured to and depend from a supporting plate or frame 30fwhich rests upon inwardly extending flanges 3l31 secured to the end walls of the casing. Between the fans is located an electric motor 32 which is similarly suspended and which is provided with oppositely extendin shaft sections 3333 for operating the Ians in unison. The fans discharge upwardly through discharge openings located below the outlet grille l5, and it is preferred to pro vide a filter 34 which extends between the fan discharge and the grille for the purpose of filtering the air before it is discharged into the room, although the filter may be dispensed with where its employment is not required. Steam is supplied to the radiator group through a steam pipe 35 controlled by a valve 36.

In operation, especially in the early morning in cold weather Where it is desired to rapidly heat a school room or the like prior to the school session, the gate valve 19 will be thrown into the dotted line position to confine the admission of air to that derived from the room, which is thus recirculated and rapidly heated without Waste of fuel due to the admixture of cold outside air. Also, under these circumstances, it is desirable to regulate the steam valve to admit steam at suflicient pressure to heat all three of the radiator sections. Under this adjustment, the operation of the fans will serve to suck the air through all portions of the radiator group, so that the air will be uniformly heated and the air streams commingled by the action of the fans and afterwards discharged upwardly through the outlet.

After the room has been preliminarily heated to the desired degree, the steam valve may be regulated to supply only sufiicient steam to heat one or two of the radiator sections, and at the same time the gate valve and damper may be adjusted to admit a pro portionate amount of outside air. In these circumstances, streams of hot and'cold air will be simultaneously admitted to the base of the heating and ventilating unit through respective indoor and outdoor inlets, and these streams will be sucked upwardly from end to end of the radiator group by. the action of the fans. Despite the fact that one or two of the radiator sections will be out of commission through the radiation of the steam supply, the streams of air will, nevertheless, be uniformly subjected to the same heating influence throughout the entire length of the heating and ventilating unit, in view of the fact that the radiator sections are all of equal length. and each extends from end to end of the will, therefore, be no tendency to heat the air at one end of the casing and to deliver unheated air at the opposite end, which would occur if the radiator sections were grouped in such a way as to locate the sections in tandemrelation from end to end of the casing. Furthermore, by locating the fans above the radiator group, and by suckingthe air upwardly through the radiator instead of forcing it upwardly from below, the air streams are brought more uniformly and intimately into contact with all portions of the radiator group, sothat uniform conditions will be maintained throughout the length of the heating and ventilating unit.

By grouping the radiator sections in the manner indicated, and by connecting them in series, it is possible to regulate the steam supply in'such a way as to retain the desired number of sections or units in service with out materially disturbing the uniformity of heating conditions throughout the length of the heating and ventilatlng unit, and without making provision valve control of the radiator sectionsi The heating and ventilating unit of the present invention is designed especially with reference to the requirements of the heating system in which heat is conserved by the heated recirculation of indoor air under proper valve regulation, and in which outdoor air is admitted only when'it is required to temper or reduce the temperature to avoid overheating, and especially in instances where the presenceof' a large number of pupils in a school room occasionally necessitates the admission of outdoor air to prevent an excessive elevation of temperature due to the body heat of occupants of the 'rbom. In these circumstances, it is particularly desirable, when the admission of cold outdoor air is necessie tated, that adequate provision be made to avoid cold air streams and to insure uniformity in the temperature of the entire" casing. There for the individual" volume of air discharged upwardly into the room. a

In view of the fact that these ventilating units, conformable to school requirements, must ofnecessity be somewhat long in proportion to the height and depth, it is particu- 'larly important to utilize radiator sections absorbed, with the result that one end of the 1 radiator remains heated while the opposite end becomes rapidly cooled, with the resulting streakiness of the air discharged through the radiator and into the room. The present improved radiator construction overcomes this difficulty by enforcing distribution of the steam, so that if only enough steam is used to heat one-third of the entire radiator group it will nevertheless be sufiicient to heat at least one of the radiator sections throughout the full length of the casing. If less than one-third heat is requiped, the out-- side air will. ordinarily be so mild that very little danger of cold streaks of air or drafts may be feared even though the radiator section is not uniformly heated from end to end.

Although the invention has been described withparticularity to details, it is not the intention to limit the invention to the details shown and described, since variations may be introduced without departing from the spirit of the invention.

I claim: a

1. In a unit device of the class described, the combination of a casing having located on its interior a radiator group consisting of sections extending longitudinally of the casing and located in lateral relation to one another, means for selectively heating one or more of the radiator sections, and means for inducing a flow of air through the radiator group a and discharging the same through the outlet, each section of the radiator group afi'ording means for a. uniform conditioning of the air stream from end to end of the easing irrespective of the number of radiator sections in commission.

2. In a unit device of the class described, the combination of a cabinet provided with an air inlet, a heating element located within the cabinet and comprising a plurality of scctions located laterally adjacent to one another, each section presenting itself throughout substantially the length of the air inlet to equally condition from end to end of the respective sections all portions of the air stream admitted through the inlet and passingthrough the respective sections, an outlet from the casingabo ethe heating element,

and means for selectively regulating theheating of the sections of the heat-ing element.

3. In a unit device of the class described, the combination of a cabinet provided with a horizontally elongated air inlet, a heating element located within the cabinet and comprising a plurality of horizontally elongated sections, each section presenting itself throughout substantially the length of the air inlet to equally condition all portions of the air stream admitted through the inlet and passing through the respective sections, anoutlet from the casing above the heating element, and means for selectively regulating the heating of the sections of the heating element.

4. A unit device of the class described, comprising a casing provided with an inlet for air and with an outlet for the discharge of air therefrom in the top portion of the casing, a sheet-metal-extended-surface radiator group consisting of a plurality of at least three relatively shallow sections, each extending substantially from end to end of the easing and the group substantially filling the space crosswise of the casing, regulating steam valve means for controlling the selective heating of one or more of the radiator sections, and suction means for inducing a flow of air through the radiator sections and through the outlet.

5. A unitdevice of the class described, comprising a casing provided with an inlet for air located near the bottom of the casing and with an outlet for the discharge of air therefrom in the top portion of the casing, a radiator group consisting of a plurality of at least three relatively shallow sections, each extending substantially from end to end of the easing and the group substantially filling the space crosswise of the casing, regulating steam valve means for controlling the selective heating of one or more of the radiator sections, and suction means adapted to induce a flow of air through the radiator sections and commingle the same prior to its discharge through the outlet.

6. A unit device of the class described, comprising a casing provided with an inlet for air and on outlet for the discharge of air therefrom in the top portion of the casing, a radiator group consisting of at least three sections, each extending substantially from end to end of the casing and the group substantially filling the space crosswise of the casing, series return bend connections between the radiator sections, regulating steam valve means for admitting steam to one of the radiator sections and for controlling the fiow of steam to one or more of the sections, and a motor and suction fan adapted to induce a flow of air through the radiator sections and to commingle the streams of air flowing through the respective sections and discharge the commingled air from the outlet.

'2'. A. unit device of the class described, comprising a casing provided with an inlet for air located near the bottom of the casing and with an outlet for the discharge of air therefrom in the top portion of the casing, a sheet-metal-extended-surface radiator group consisting of a plurality of at least three sections, each extending substantially from end to end of the casing and the group substantially filling the space crosswise of the casing, series-connections between the radiator sections, means for admitting steam to one of the radiator sections, and controlling valve means adapted to selectively heat one or more of the sections, and a-motor and suction fan for inducing the flow of air through the radiator sections and for commingling the streams of air and discharging commingled air from the outlet.

8. A unit device of the class described, comprising a casing provided with an inlet for air and with an outlet for the discharge of air therefrom in the top portion of the casing, a sheet-metal-exten(led-surface radiator group consisting of a plurality of at least three sections, each extending substantially from end to end of the casing, and series-connections between the radiator sections, means for admitting steam to one of the radiator sections, means for controlling the flow of steam to selectively heat one or more of the sections, and a motor and suction fan located between the radiator group and the outlet and adapted to induce a flow of air through the radiator sections, and to commingle the streams of air and discharge the c-c mmingled air through the outlet.

9. In a unit device of the class described, the combination of a horizontally elongated casing having front and rear walls in relatively close spaced relation to afford a relatively shallow structure provided with a horizontally elongated inlet for air near the base of the casing through one of the aforesaid walls thereof, the casing being provided with an air inlet and a horizontally elongated discharge outlet extending longitudinally of the casing in the top portion thereof, a horizontally elongated steam passage of a contour that prevents stratification of the steam vapor thereirna radiator group within the casing consisting of at least three parallel sections extending horizontally substantially from end to end of the casing and substantially filling the space crosswise of the casing, and means for selectively regulating a flow of unstratified heating medium through one or more of the radiator sections.

10. In a unit device of the class described, thenombination of a horizontally elongated casing having front and rear walls in relatively close spaced. relation to afford a relatively shallow structure provided with a horizontally elongated inlet for air near the base of the casing through one of the aforesaid walls thereof, the casing being provided with a horizontally elongated discharge outlet extending longitudinally of the casing at the top portion thereof, a horizontally elongated radiator group within the casing consisting of at least three parallel sections extending horizontally substantially from end to end of the casing and substantially filling the space crosswise of the casing, and means for selectively regulating a flow of nonstratifying heating medium though one or more of the radiator sections, and a plurality of suction fans located in spaced relation to one another and above the elongated radiator group for inducing a flow of air from end to end therethrough and its discharge upwardly through the outlet.

11. In a unit device of the class described, the combination of a casing having located on its interior a radiator group consisting of at least three horizontally elongated sections extending longitudinally of the casing and located in lateral relation to one another and substantially filling the space crosswise of the casing, series-connections between the' radiator sections, means for regulating the inflow of heating medium by a regulating Valve to the radiator group to selectively fill only one, two or more of the sections with steam, and means for inducing a flow of air through the radiator group and discharging the same through the outlet, each section of the radiator group affording means for a uniform conditioning of the air stream from end to end of the casing irrespective of the number of radiator sections in commission.

In witness that I claim the foregoing I have hereunto subscribed my name this 25th day of September, 1930.

' WILFRED SHURTLEFF. 

